The invention relates generally to the field of pattern recognition, and in particular to the retrieval of patterns from a database.
Patterns are central to the design of fabrics, textiles, wallpapers, floor mats, tiles, etc. A pattern is composed of various pattern elements. A common approach to generating different versions of a pattern is to vary the color of one or more pattern elements. For example, several versions of a xc2xdxe2x80x3 vertical stripe pattern can be created by using different combinations of two or more colors. The differently colored versions of a pattern are considered perceptually similar in connection with numerous applications. For example, it is common for a fabric designer or manufacturer to offer its customer a large selection of colored patterns, where the entire set is composed of perceptually similar patterns which vary only on the basis of color. The same is true for other colored pattern-based items. A furniture store offers its customer a choice of similar fabric patterns for furniture. An interior decorator or home manufacturer can offer a selection of similar patterns for wallpaper, tiles, etc.
In recent years, several commercial software and web-based services have been introduced in areas like interior decoration and made to order furniture or clothing, where a customer is required to select a pattern for one or more items. For example, a customer can create virtual 3-dimensional furniture with the desired fabric(s) in a selected pattern or create and decorate a virtual 3-dimensional room with selected furniture(s), wallpaper(s), flooring(s), etc. A virtual item can be created with different patterns or different versions of a selected pattern in order to make a final selection for custom ordering. In these situations, a customer or user commonly wants to view one or more versions of a selected pattern in order to make the final selection. For example, a decision on wallpaper may require a customer to view one or more of different available versions of a desired pattern. In these and similar applications, a person making a final decision on the pattern of an item generally employs a two step process for the selection of a specific pattern. First, a desired pattern is selected or provided. Then a version of the selected or provided pattern is selected. The second step of the selection process, that is, the selection of a specific version of a selected or provided pattern, requires a decision-maker to view different versions of the selected or provided pattern.
Current software or web-based systems and applications generally employ one of the following two approaches for identifying patterns that are perceptually similar to a given pattern:
(a) predefined groups of perceptually similar patterns are stored in the system, with each pattern including a reference to the parent group with which it is also associated. Given a pattern, the referenced group provides the perceptually similar patterns;
(b) a user is required to review an entire database to identify different versions of the selected or provided pattern.
Both these approaches have several shortcomings. For a sizable pattern database, the second approach can be very taxing and frustrating for a user. The first approach is very taxing for the system and/or pattern designer who define(s) the groups of perceptually similar patterns. Mistakes made in defining the groups could lead to unexpected results and customer dissatisfaction. Furthermore, the addition and/or deletion of new patterns requires modification of the pattern groups, which may prove to be commercially uneconomical and/or impractical.
Therefore, automatic, feature similarity based pattern search and retrieval systems are needed for identifying perceptually similar patterns. However, none of the existing feature similarity based search and retrieval techniques are well suited for automatic pattern similarity-based search and retrieval. In U.S. Pat. Nos. 5,579,471; 5,852,823 and 5,893,095, search and retrieval techniques are based on color feature similarity. In a system for selecting decorative materials described in U.S. Pat. No. 5,751,829, spectrophotometric color referencing allows data records to be searched on the basis of color, as well as other information that was entered into the record. Wallpaper patterns, drapery material, floor covering or paint can then be selected on the basis of matching color. Various patterns and paints can be compared side-by-side and rendered onto a room image so that the consumer can view an accurate simulation of the chosen materials. However, color feature similarity-based methods described in these patents are not suited because they identify similar images based on the similarity of color contents or color properties. Since color properties of different versions of the same patterns usually vary, color similarity cannot be employed to identify and retrieve similar patterns. Texture feature based methods disclosed in the first three patents are not suited because they determine image similarity in terms of monochromatic textural properties of patterns. Since several different colors reduce to the same monochromatic value, the patterns in the monochromatic versions of two different color versions of the same pattern can differ and hence would not be considered similar.
What is needed, since color and texture properties of different versions of the same patterns usually vary, is a system that can be employed to identify and retrieve similar patterns irrespective of color variations.
It is an object of the invention to provide a system and a method for automatic search and retrieval of patterns similar to a given pattern.
Assuming that each colored pattern is available as a digital image, it is a further object of the invention to provide for automatic search and retrieval of digital images that are computer generated synthetic images of patterns or digital images of full patterns from the actual items (i.e., fabric, tile, or wallpaper).
The present invention is directed to overcoming one or more of the problems set forth above. Briefly summarized, according to one aspect of the present invention, the invention includes a method for retrieving digital patterns similar to a query pattern by generating representations of each digital pattern in terms of one or more color invariant properties; storing and organizing the patterns and their representations in a database; and searching the database by reference to the representations to identify and retrieve patterns similar to the query pattern. A preferred color invariant property is an edge property of each digital pattern, and more particularly its edge orientation.
The advantage of this invention is that it provides a system for organizing a database of patterns by color invariant properties, such as an edge property. Patterns and colors are crucial to the design of wallpapers, fabrics, textiles, floor mats, tile, rugs, etc. These items are usually available in different colored versions of the same pattern. In other words, different versions of the same pattern are created using different colors for the pattern elements. What this means is that different colored versions of a pattern are considered to be similar patterns. In applications such as fabric selection for furniture or clothing, wallpapers, floor mats, rugs, window treatments, and tile selection in an interior decoration application, different colored versions of a selected pattern are usually reviewed. Such a review requires identification and retrieval of the set of patterns similar to a selected pattern, and at least initially irrespective of color.